1. Field of the Invention
The invention relates to a method for feeding a gas turbine with both liquid and gaseous fuels.
2. Discussion of Background
Conventional gas turbines, if they are operated with both liquid and gaseous fuels, have separate feed paths for each type of fuel. For the combustion of gaseous fuel, premix burners are generally used, in which gaseous fuel is mixed with the combustion air in premixing zones and is combusted. If liquid fuel is used, it is injected into the premixing zone through one or more nozzles.
However, mixing of the injected fuel with the combustion air is insufficient, in particular because it is not possible to keep the droplet size sufficiently small. Moreover, the use of two separate feed paths is technically very complicated, without as a result improving the performance of the gas turbine. It has not to date been possible to use both types of fuel in a single feed system, since there are very different impulse ratios at the gas inlet into the combustion chamber with the same amount of power supplied, owing to the different volumetric calorific values of liquid and gaseous fuels.